1. Field of the Invention
The present invention relates to error correction devices to be used in physical property value detection devices comprised of a detection element, a modulation section and a detection section. The detection element detects a value of a physical property of a detection target, and outputs detection signals relating to the detected value of a physical property of the detection target. The modulation section modulates the detection signals outputted from the detection element into pulse signals, and outputs the pulse signals. The detection section receives the pulse signals transmitted from the modulation section through a pulse signal transmission path, and detects the value of the physical property of the detection target on the basis of the received pulse signals.
2. Description of the Related Art
There have been proposed and used various types of error correction devices. For example, Japanese patent laid open publication No. JP 2009-171312 has disclosed an error correction device having a conventional structure comprised of a temperature sensing diode, a modulation circuit and a microcomputer as a detection section. The temperature sensing diode detects a temperature of a detection target (a semiconductor switching element, for example a power switching element, etc.) and generates and outputs detection signals relating to a detected temperature of the detection target. The modulation section receives the detection signals transmitted from the temperature sensing diode, and modulates the received detection signals to pulse signals. The microcomputer as the detection section receives the pulse signals transmitted from the modulation circuit through a photo-coupler mounted on a pulse signal transmission path, and detects a temperature of the detection target on the basis of the received pulse signals.
In general, when noise is added to the pulse signals on the pulse signal transmission path to which the photocoupler is mounted, such noise added into the pulse signals often cause the microcomputer to decrease a detection accuracy of the temperature of the detection target.
Various types of physical property value detection devices have the above problem of decreasing or deterioration of the detection accuracy caused by noise so long as these detection devices detect a value of a physical property of a detection target on the basis of detection signals transmitted through a transmission path which has a photocoupler, where the detection signals relate to a value of a physical property of the detection target detected by a detection element such as a temperature sensing element.